Omc 15a fuel oil mixture

[PoseidonX]

Im in the process of getting my own ASH rig with OMC 15 motor A. I understand the OMC 15 A is Two stroke. What would be the correct oil/gas mixture ratio to make it run smoothly and I understand with today fuels ethanol is a Pain when they check the fuel with a meter. Is there anywhere where I could get regular gas with out ethanol?

[WalkWithMax]

Oil Mix

Here's my understanding of oil mixing...

You will likely get some differing opinions on this. It seems most guys are mixing 25:1. As far as oil goes, BRP 2 cycle conventional outboard oil is good as well as Yamalube, BRP or other name brand semi-synthetic oils, but a lot of guys swear by Amsoil Dominator synthetic.

Gas is dependent on where you live which I am not too sure about in terms of ethanol content, etc.

[Shane_B]

Ethanol Free Gas

Right about getting DQ'd using fuel with ethanol... to find stations offering ethonal free fuel near you, can google it (ethanol free gas station locations) or go to www.local.com and put "ethonal free gas stations" in "SEARCH" and your location in the "NEAR" block. Local racers should also be able to assist you in your efforts.

Fuel mixture for a 2 stroke outboard is normally 30:1 ratio per factory specs (as is for a Y302) but can be different based on type oil used (for instance, some synthetic two-stroke oil mixes can be greater than 30:1 ratio). Recommend getting with local ASH racers to determine fuel mix/rich/lean settings for your specific engine setup.

[sponsonhead]

There's an App for that!

There's an App for that:

http://pure-gasoline.com/

R-19

[PoseidonX]

Now does Octane play any role in the gas. Does it affect anything? I've seen like the sunoco sign saying ethanol free but the octane was like 110..i was like wow

[bmitch1]

Octane is the ability of the fuel to resist detonation (commonly referred to in the car world as 'knock') - where some or all of the fuel under pressure in the cylinder is igniting at a less-than-optimal point in the stroke. The result of knock can destroy cylinders, crack the ring-lands out of pistons, and wreak havoc on the durability of the motor.

Typically higher octane is needed in turbo/super-charged applications or higher compression engines where the combustion process is more "powerful", but naturally-aspirated race motors with large combustion chambers perform well with high-octane fast-burning fuels too. Interestingly, F-1 (car) racing engines have compression ratios exceeding 18:1 and run nearly 20,000 RPMs but they only use an average 96 octane fuel.

Ethanol is less powerful than an equivalent amount of gasoline - having roughly 66-67% the energy of an equivalent amount of gasoline. But ethanol actually improves the ability of the fuel to resist detonation - which is why ethanol fuels get a higher octane rating. Some of the guys with turbocharged cars actually switch to high-capacity injectors and high-volume fuel pumps with e85 (85% ethanol) and can get tremendous horsepower with less risk of engine-destroying knock than traditional 93/94 octane pump gas.

[SeaBat]

We've been running 32:1 Red Line 2 Cycle Racing with non-ethanol regular or premium. Some gas dealers only have non in premium. Anything above regular is not an advantage in the A Stock OMC or Mercury. Some APBA race sites will allow the fuel of the day E10 and specify a fuel source near the race site as the basis for the test sample. We stick to non-ethanol that way we are always legal.
Bill

[Roskowski30h]

We have been running 20:1 using either Klotz or Amsoil synthetic. Typically we run regular pump gas, but for things like nationals, divisionals, and North Americans we will get aviation fuel from our local airport to be 100% sure it's legal.

[PoseidonX]

Aviation fuel..Never thought of it. I live like 2 min away from Groton-New London Airport just off long island sound.

[krazy karl]

Aviation fuel..Never thought of it. I live like 2 min away from Groton-New London Airport just off long island sound.

I used to take my dad to that airport in the 60's when he went on a business trip. We lived on Mason's Island in Mystic.
kk

[pops67g]

There's more to it.....

Motors that are older were not made with materials (in the fuel system) that were compatible with alcohol, so parts in the carbs and fuel pumps deteriorate and fail fairly soon. Our stock racing motors have the same compression ratios as the fishing versions so high octane fuel is basically a waste of money and you still don't get rid of the ethanol. Spark plugs with a colder heat range do more to prevent misfire than higher octane fuel. In Minnesota we get ethanol free fuel and it is 91 octane (our only choice). The biggest problem is that only a few gas stations sell it and it's usually 50 cents or more a gallon higher in price.

The oil mix issue has been thrown around numerous times here so you will get as many different answers as there are contributors. I run 8:1 in my 4 cylinders and it works really well. The extra oil helps seal the rings better for more power. And with the elevated RPM's that we run oil is definitely cheaper than parts.

[Graham]

Oil Mixture OMC 15

We won Nationals using 6 oz. AMSOIL per gallon and Aviation Gasoline LL100.

Don Graham

[PoseidonX]

We won Nationals using 6 oz. AMSOIL per gallon and Aviation Gasoline LL100.

Don Graham

Nice jOB! congrats!!

[ricochet112]

We've been running 32:1 Red Line 2 Cycle Racing with non-ethanol regular or premium. Some gas dealers only have non in premium. Anything above regular is not an advantage in the A Stock OMC or Mercury. Some APBA race sites will allow the fuel of the day E85 and specify a fuel source near the race site as the basis for the test sample. We stick to non-ethanol that way we are always legal.
Bill

Bill, E85 is 85% ethanol. The fuel at the pump is E10, 10% ethanol. An engine must be specifically designed to run on E85.

We run OMC XD30 or XD50 at 32:1

I will not run any ethanol through any of my engines, except my cars, ethanol WILL damage carburetors, unless you flush out all the ethanol fuel after every running before it sits. Ethanol is a solvent and it will draw moisture and it's very corrosive.

[T Chance]

In my 12 year old granddaughter's K-Pro (same OMC 15 hp motor as your A Stock) we run 4 oz of Red Line Synthetic 2-Stroke Racing Oil to One gallon of Sunoco alcohol free racing gasoline. The gas is overkill for the motor but it is easy to get as I buy it from the same source as I get my methanol for my Pro motors.